The worst time to move them is while they are
leafing out, when they are in full bloom, or if they are severely
stressed by drought, or insect or disease problems. That is because they are
using their carbohydrate reserves in order to push new growth and
bloom, or to survive stressful situations. The added stress of
severing a large portion of their roots and moving them to a new
site can be overwhelming.
Have their new site prepared so that you can dig them and replant
them immediately. The new location should provide shade from hot
afternoon sun and well-drained soil. None of the plants you listed
will tolerate poorly drained soil for long. Have the soil tested so
that you can till in fertilizer and soil amendments prior to
planting. It would be ideal if you create a new bed that will
encompass all of these plants rather than planting them
individually. That way, you can till up the entire area and amend it
with several inches of organic matter such as compost or well-rotted
manure, along with fertilizer and pH amendments as recommended by
your soil test.
If you move them this spring, you will not have time to root prune
them. Root pruning is the practice of gradually severing roots
around the circumference of the rootball you plan to dig prior to
actually digging it. This allows fine feeder roots to fill in the
rootball, which helps reduce transplant shock. The fall prior to
transplanting is the ideal time to root prune. You can root prune
one-third of the circumference, wait a month and root prune the
second third, wait another month and root prune the final third. Or
you can root prune around the entire circumference by sticking your
spade in every other space, so that it looks like a dotted line.
Wait a month, then root prune the spaces left the first time around.
A spade's depth is sufficiently deep for root pruning. However,
there is no point trying to root prune now, since root development
ceases when soil temperatures fall below about 40-degrees F. You
might be able to start in early March and get them partially root
pruned prior to moving them in late March or early April, but I am
not sure the resulting root development will be sufficient to
warrant your effort.
Removing the bindings from
a commercially dug pine
When you dig them, take as much of the root system as humanly
possible. Transplant them immediately into the new bed. Make sure
you do not plant them any deeper than they were growing before.
Water them in thoroughly, and mulch with two to three inches of
shredded hardwood bark out to the ends of their branches. Be sure
the mulch does not physically contact the stems of the shrubs. Check
them several times a week, and provide supplemental water as needed.
You do not want to overwater them, but you should never allow them
to dry out completely, either. Stick your finger in the soil around
the base of each new transplant to see if the soil is moist. If it
is, do not water; if it is dry, go ahead and water. As they become
established, you can begin water more deeply and less frequently.
You can prune the shrubs back a little if necessary to make them
more manageable (especially the huge rhododendron), but it is no
longer recommended that woody plants be pruned severely when they
are transplanted. Horticulturists used to believe that pruning the
topgrowth back hard at transplanting helped balance the severely
reduced root system. However, current research has shown that
transplants need as many leaves as possible to photosynthesize and
produce the carbohydrates needed to regrow a complete root system.
in Late Fall
Plants for Street